Process of making hollow balls



Nov. 11 192.4. 1,514,810

. w. J. wlscH PROCESS OF MAKING HOLLOW BALLS F iled Dec. 22, 1920 3 Sheets-Sheet 1 amwwto'z mzzier J VVi'sch,

W1 r/vsss NOV. 11 1924,

W. J. WISCH PROCESS MAKING HOLLOW BALLS Filed Dec. 22 1.920 55 Sheets$heet 3 l-noewtoz llll I= fl Zzfier J M5070) Nov. 11, 1924.v 1,514.810

, w. J. WISCH PROCESS OF MAKING HOLLOW BALLS Filed DeC. 22, 1920 3 Sheets-$21891. 5

INVENT'OR n aslier n seh,

, f J I Patented Nov. ll, i924.

barren siaaie WALTER J. WISCE, OF BALTIMORE, MARYLAND.

PROCESS OF I/IAKING HOLLOW BALLS.

Application filed December 22, 128. Serial No. 432,466.

To all whom it may concern:

Be it known that -WALTER J. Wilson, a citizen of the United States, residing at Baltimore city, State of Maryland, has invented 5 certain new and useful Improvements in Processes of Making Hollow Balls, of which the following is a specification.

My invention relates to a method of making balls, and especially to an improved method of economically producing hollow balls of exceptionally desirable characteristics.

A leading characteristic of my improved method consists in simultaneously hammering or pounding, and rolling, the partly formed balls to bring them to the desired final form. The causes the metal of the ball to How so that the opening isclosed, in an improved manner, and the wall is brought to a remarkably uniform thickness throughout. llhe closure of the opening is very complete and hoinogenous, so that the substance of the hollow ball is continuous and of substantially uniform strength throughout. The complete balls are furthermore characterized by absence of any definite or considerablc inner peak or projectionof metal at the place previously occupied'by the open- .ing in the partly finished ball. cases, if the combined rolling and hammering operation is continued to a sufficient extent, a minute annular ridge is formed on the inner surface of the ball at a point sur-' rounding the previous location of the opening. If the finishing process is discontinued shortly before the point just described, this small annular ridge is absent, and instead there is a slight depression in the inner surface of the wall at a point corresponding 40 with the previous location of the opening.

Another characteristic of the process con-.

sists, in some cases, in making the hollow blank in a slightly elongated or ovoid form, and utilizing this ovoid form of the blank in effecting the combined rolling and hammering action.

Another characteristic of the process consists in forming the hollow blank in certain of its stages with its wall substantially thicker, adjacent to the opening, than other parts of the wall.

Other characteristics of the process will be sufficiently explained in connection with In some a detailed description of one complete performance of the process as carried out by representative apparatus, sufficient parts of which are shown in a diagrammatic way in the accompanying drawing.

Figures 1 to 10 inclusive are transverse sections through the ball blank and ball, in diflerent stages of its progress from the first formation of the blank to completion of the ball. The difierent steps are explained hereafter.

Fig. 11 is a transverse section of one representative forming device used in the combined rolling and hammering of the blank to close the opening and otherwise shape the ball.

Fig. 12 is a plan view of one of the members of Fig. 11. In these two figures, the rolling members are straight bars or plates provided with straight grooves.

Fig. 13 is a diagrammatic view of rotary rolling members, in which the rolling plates are circular and the grooves are of annular form.

14 is an elevation, with some parts in section, of a rolling and hammering machine arranged for rotary movement of the plates.

1 shows the first step in the formation of the blank, consisting in punching or pressing a piece of sheet metal in suitable dies into cup form, the dies being usually arranged so that the upper, cylindrical part 1 of the wall V is made slightly thicker than the lower, hemispherical part 2.

Fig. 2 shows the blank pressed deeper. The thickness of both parts 1 and 2 of the shell has been somewhat decreased, and the difference in thickness between the two parts has been somewhat increased. Fig. 3 shows continuation of the pressing in which the cylindrical part 1 is elongated still more, and slightly reduced in thickness, and the thickness of the hemispherical part 2 is fun ther reduced, and the difference between the thickness ofthe two parts is still farther increased. Fig. 4 shows the blank in the same condition except that the ragged upper edge 3 of Fig. 3 has been trimmed offsmootlnthe height of the trim beingcalculated with reference to the size of the opening which it is desired to preserve in the blank up to the point of rolling or hammering. Fig. 5 shows the blank after being treated in suitable forming dies, so that it assumes a general egg shape, the upper portion 53 now being curved inwardly toward the opening 6. In this operation, the thickness oi the wall of ovoid part 5 increases gradually from the diameter (Z to the edge of the opening 6, and the average thickness of this part of the blank is decidedly greater than that of the hemispherical portion 2. Due to the compression or" the metal in the direction of the vertical dimension of the blank in this forming operation, thethickness of the hemispherical portion has been increased somewhat, and the average thickness of part 5 has been increased still more markedly in comparison with the thickness or part 1. is clearly shown, the thickness or part 5 increases gradually and rather unitormly from the diameter cZ- to the limits of opening 6. 6 shows further forming operation in which the thickness of both parts of the blank has been increased, but the thickness of the ovoid portion adjacent to the opening has been increased in an ascending ratio so that the difference in thickness between the metal adjacent to the opening, and the thickness of portion 2 is markedly increased. 7 shows the blank after treatment in another suitable forming die in which the entire blank is still further compressed lengthwise, so that part 5 is now approximately spherical, although slightly elongated, the dimension 0 being slightly greater than the dimension f, which i s-a radius of the hemispherical part 2. he thickness of the wall of tl'ieblank'has also been increased throughout, and the thickness of the part adjacent to the opening 6 has been increased still more in relation to the thickness 01 the hemispherical portion. The rate of increase of the thickness of part 5 oi the shell is graphically shown in Figures 5, 6 and 7, with some exaggeration, since it is impossiblein views of reasonable size to show relative dimensions accurately. r

The previously described steps may be regarded as preliminary steps, and are analo 'ous to known methods of producing blan .3 for final rolling, except with regard to the: particular dimensioning of the shell described to adapt it especially to the final rolling and hammering process, and. particularly with regard to the. final formation of the blank as shown in Fig. 7 with substantially one-half of slightly increased radial depth than that of the other, which is hemisphere, theradial depth ofthe elongated portion being measured at the. center.

of the opening. lVl nle the blank as preliminarily formed m Fig. 7 is preferred for the final process described justhereafter, I .do. not limit myself to the preliminary formation of blanks in the precise form shown. Any other suitable blank of approximate spherical form and substantial wall thickness, and having an opening of suitable size, may in some cases be treated by the final rolling and hammering process to close the opening, and render the tiickness of the wall sufiiciently uniform throughout,

Considering the blank in a preferred final preliminary form as shown and described in connection with 7, a suitable number of such blanks are placed in a rolling channel C, l 11, which consists of two grooves, g and 9 formed in bars or plates 20, 21 respectively. These plates may be straight, as shown, in a representative form of ap paratus for carrying out the process, and

oves may be straight, and the roll- .onnment of the two plates and their ctivc grooves may be a relative linear retprocatory movement produced by any suitable mechanism. As the grooves reciprocate carrying the balls back and forth tween them under suitable pressure exerted through the plates by any suitable means, the balls in addition to this rolling,

treatment are subjected to a simultaneous pounding or hammering, which may be effected in various ways. Where the blanks are of elongated or ovoid form as abovedescribed, the hammering effect may be obtained to a sutlicient degree by rolling the balls in smooth grooves. The blanks are continually presented to the grooves in different positions, and due to their unequal dimensions are bumped or hammered in;

the grooves until they are reduced to true finished form. In cases where the elongaoi the blanks is insutlicient to produce 5 result, or where spherical blanks are somewhat greater di meter than that of the groove. The depressions so produced, by whatever .means, are substantially oval lateral depressions in the main groove surface. The blanks therefore, as they are al- .ternately rolled back and forth between the plates in the channel Q are subjected to the rolling and compressing action of both 0? the grooves, and simultaneously, to bumping or hammering as the balls encounter the edges of depressions 25.

Various refinements may desirably be made one representative way of pounding Lil Ill

in the form of thegrooves. I The main portion of the smooth groove 9? is preferably formed. on a circularradius from the center :12.

Preferably each of the grooves is formed with a lateral relief near the sides of the grooves. This may be provided by making in the side wall of each groove a bevel 26, which may be cut at an angle of degrees, more or less, in relation to avertical dimension, intersecting the groove proper at a point a suitable distance inward from the main plate surface. f

By the treatment in the rolling and hammermg grooves, the ovoid blank goes through the changes indicated in Figures 8 and 9. Groove g of true semiecircular section controls the spherical shaping of the entire ball. Th irregular groove 9 by its combined rolling and hammerin action swages. or flows down the metal of the ball shell from the form shown in Fig. 7 to the form shown in Fig. 8 and then in Fig. .9; i. e., the metal of the wall is formed orv caused to flow until it assumes uniform thickness, and simultaneously the metal'surrounding the opening 6 is sWa-ged and flowed inwardly until the surface metal joins at 10, Fig. 9, leaving a shallow inner depression 11. The ball isthen complete, of true spherical form and with uniform wall thickness, and with an unbroken homogeneous surface, but slightly larger than the preferred final diameter, and with the opening truly closed, but not in the usually preferred final form. While the balls may be used in the condition shown in Fig. 9, it is generally preferred to give them a final treatment in smooth finishing grooves, such as the grooves 9 9, formed respectively in roll lates 20 and 21, constituting a channel C of true circular cross section except for lateral relief cuts 28 provided on the edges of the grooves, the same asin the case of g By reciprocation of the plates, the balls are rolled down in these grooves to the form shown in Fig. 10. The diameter of the balls is slightly reduced, the wall thickness slightly increased and left uniform, and the opening is completely closed, leaving the inner surface of the ball almost flush at the point where the opening was formerly, or 'else leaving a" very slight annular ridge 12 surrounding an area 13, which has a radial thickness substantially the same as other parts of the wall.

Instead of straight rolling plates, the plates may be made circular, with annular grooves as shown in Fig. 13. The grooves constituting the two channels C and C have all the characteristics described in connection with Figures 11 and 12, and are substantially the equivalents of those grooves, arranged in circular form for continuous circular rolling, in which the two plates may be revolved in pposite dir ti ns, or either one may be held stationary and the other rotated continuously in either direction or oscillated in alternately opposite directions.

Fig. 14 shows in suflicient detail one complete machine for carrying out the final steps of the process,and also shows a modification of the combined rolling and hammeringoperation. For this purpose one of the plates, for instance plate 40, is held stationary, and the other plate 41 is revolved by means of a shaft 42, and gears 43. The plate 41 is also free to move vertically in relation to plate 40, and suitable vertical movement .or' reciprocation is imparted to plate 41 by an annular cam surface 44 on the plate, this surface being in wave formation with alternate humps 45, and hollows 46, shown in exaggerated form in the figure. The frame 47 carries one or more, usually a plurality of cam rolls 48, mounted on pins 49 in the frame, andthese rolls are spaced uniformly about the rotative center. All of the grooves in this instance are made smooth, and of substantially semi-circular cross section except" for the relief cuts 26 provided as previously described. The grooves g g constituting channel C for the firstrolling and hammering operation are formed at a slightly larger radius than 'rooves g 9 which constitute channel C 1.01 the final operation. The rolling of the balls in channel C is conducted in an obvious way, and they are simultaneously pounded or hammered by the action of cam rolls 48 on the cam surface 44, giving an effect substantially like that of the irregular groove g? of Figures 11 and 12. The finishing rollingin channel C may be a simple rolling operation as described in connection with Figures 11 and 12, or it may be a combined-rolling-and-hammering operation. Evidently, the different rolling operations may be carried out in different machines, so that if desired,one machine may be arranged for the combined rolling and hammering operation, and another machine may be arranged for a final smooth-rolling operation. f

The process as above described in connection with the machine of Figure 14 is adapt ed for rollingspherical blanks, or other blanks where the non-spherical form of the blanks themselves is not considered suflicientto provide the necessary hammering action. Where ovoid blanks, as described above, are used, sufficient hammering effect may be obtained in most cases, as previously suggested, by rolling the ovoid blanks in smooth grooves. without the cam surface 44 and camrolls 33; and the machine of Figure 14 may be adapted for this method of rolling by removing the cam rolls 48. Preferably also the. bearing 50 which accommodates shaft 42 is made, as shown, with considerable clearance, from the shaft, This permits the movable rolling plate to have a certain amount of lateral freedom, and to position the grooves to the best advantage with regard to the momentary position of the blanks.

I I claim l. The process of rollinghollow balls, comprising simultaneously rolling and hammering at right angles to the path of the rolling movement, a hollow globular blank, the hammering being continuous and substantially uniform during the entire operation.

2. The process of rolling hollow balls, comprising forming by successive preliminary operations a hollow metal shell, approximatelyspherical, with. an openin at one point, and. then simultaneously rolling and hammering the blank at right angles to the path of the rolling movement to close the opening, and complete the shaping of the ball, the hammering being continuous and substantially uniform during the entire operation.

'3. The process of making hollow balls,-

comprising forming sheet metal into approximately spherical torm with an opening atone point, the wall or the blank a(l jacent to the opening being somewhat thicker than other parts of the wall, and then simultaneously rolling and hammering the blank until the opening is closed and the thickness of the wall is rendered substantially uniform throughout.

if-The process of making hollow balls, comprising forming sheet metal into approximately spherical torm with an opening at one point, the. part of the blank containing the opening being slightly elongated or. ovoid, and the other part being more nearly truly hemisphericah and then rolling the blank and simultaneously hammering it to close the, opening by knitting the metal homogeneously together, and reduce the ovoid portion to approximately true hemiv spherical form.

5. The process of making hollow balls,

comprising forming sheet metal into ap- I rolling and hammering the finally proximately spherical form with an opening atone point, the part of the blank containing the opening being slightly elongated or ovoid, and the other part being more nearly trul hemispherical, the wall adjacent to the "opening being" substantially thicker than portions ot the wall more remote from the opening, an'clthen rolling the blank and simultaneously hammering it to close the opening by knitting the metal homogeneously togethe', and reduce the ovoid portion to approximately true hemispherical form, and to flow the metal of the wall away from the thicker portion, so that the wall is I'GQlUCBClsfO substantially uniform thickness ,throughont.

6. The. process of making hollow balls, comprising forming a sheet metal blank with an opening atone place, simultaneously lankto flow the metal ancl partially close the opening and to reduce the blank to nearly its final 'rlian'ieter with the wall of nearly uniform thickness throughouaancl then rolling the blank to reduce it to final diameter and thickness and to complete the closing of the metal at the former location of the opening. I i

7. The n'ocess of making hollow balls comprising forming a substantially I cupshapecl blank, maintaining the closed part of the blank in substantially nemispherical form, and compressing the other part of the blank into substantially ovoid form and simultaneously increasing the thickness ot the Wall as it approaches the opening, and compressing the blank, until the ovoid portion in its longitudinal axis is only slightly longer thanthe radiuso'f the hemispherical portion, retaining the opening in the ovoid part of the blai'ik in line with the longest axis of theblank, the wall of the blank adjacent to the opening being sub stantially thicker than other parts of the wall, the blank thus formed being adapted for final treatment by combined ham-mering and rolling. y i

In testimony whereof I affix my signature.

' WALTER J4, l VlSC-H. 

